Electrical warning system



N 1, 1 c. H. POMEROY 3,010,098

ELECTRICAL WARNING SYSTEM Filed May 25, 1959 2 Sheets-Sheet 1 INVENTOR B anima e, arm/10 ATTO EYS Nov. 21, 1961 c. H. POMEROY ELECTRICAL WARNING SYSTEM 2 Sheets-Sheet 2 Filed May 25, 1959 KRQ INVENTOR United States Patent Ofifice Efildfi Patented Nov. 21, 1961 3,010,098 ELECTRICAL WARNIN G SYSTEM Claude H. Pomeroy, Mesa, Aria, assignor to Ponieroy Circle Centers, Inc Mesa, Ariz. Filed May 25, 1959, Ser. No. 315,574 Claims. (Cl. 349-224) My invention relates broadly to radio receiver systems and more particularly to a warning device responsive to Conelrad frequencies.

One of the objects of my invention is to provide an arrangement of a portable transistorized electronic device arranged for continuous standby operation on Conelrad frequencies for tripping warning alarm upon activation from a Conelrad frequency.

Another object of my invention is to provide a transistorized circuit for a warning device operative by Conelrad frequencies and including an alarm operative upon reception of a Conelrad frequency and wherein the circuits of the device may be normally powered from the conventiona1 alternating current power circuit but including means for automatically transferring the power circuits of the device to battery supply in the event of interruption or destruction of the alternating current power supply. systern.

Another object of my invention is to provide a Conelrad radio receiver having a readily connectable or disconnectable replaceable tuning unit selectively and efiiciently responsive to either of the Conelrad frequencies, that is, 640 and 1240 kc. for rendering the receiver more selective on either of the Conelrad frequencies in the particular area in which the receiver is being operated.

A still further object of my invention is to provide an arrangement of transistorized radio receiver alarm system including means for readily testing the condition of the power supply circuits of the receiver and alarmfr'om time to time in order that the effectiveness of the receiver and alarm for standby operation on the Conelrad frequencies may be checked from time to time for eliminating a condition where the power supply circuits might become ineffective to function the receiver or alarm at a time of disaster or sneak attack when the functioning of the receiver is of prime importance.

Other and further objects of my invention reside ina rugged and reliable arrangement of warning device for operation on the Conelrad frequencies, powered from either battery sources or conventional power systems as set forth more fully in the specification hereinafter following by reference to the accompanying drawings, in which:

FIG. 1 is a schematic circuit arrangement of the transistorized radio receiver system of my invention as embodied in. a miniaturized portable radio receiver and alarm including the testing circuits for checking the condition of the battery from time to time and illustrating particularly the connectable or disconnectable readily insertable tuning unit for selectively tuning the receiver to one or the other of the Conelrad frequencies;

FIG. 2 is a schematic view of a substitute tuning unit selectively responsive to one of the Conelrad frequencies and which is readily insertable into the tuning circuit of the receiver of FIG. 1 in substitution for the tuning unit in that circuit which is more selectively responsive to the other of the Conelrad frequencies;

FIG. 3 diagrammatically illustrates a circuit arrangement embodying my invention in which the power circuits to the receiver and the alarm may be Supplied from the conventional alternating current power system and upon failure of such power supply automatically switch the receiving circuit and the alarm circuit to battery power for continuous operation of the system under battery power regardless of the possible interruption or destruction of the alternating current power system, the view showing the removable and replaceable tuning unit for providing greater selectivity for response of the receiver to one or the other of the Conelrad frequencies; and

FIG. 4 is a view of the readily connectable and disconnectable replaceable tuning unit used in the circuit of FIG. 3.

My invention is directed to an arrangement of Conelrad initial warning device for homes and buildings readily applicable to vehicles and portable miniature radio receivers. I provide a transistorized circuit requiring minimum consumption of electrical power and having long extended term of reliable operation unhindered by necessity of tube replacement. The receiving circuit includes a tuning unit which is particularly effective at the Conelrad frequency for the particular area in which the receiver must function. The receiving circuit when operated in certain areas often functions more effectively on one of the Conelrad frequencies than'on the other and the receiving system of my invention is provided with that kind of a tuning unit which may be readily inserted into the circuits of the receiver for producing the most effective response for such receiver in the locality in which the receiver must operate.

I have found, after checking conditions in many areas of the United States, that the Conelrad frequencies of 640 kc. and 1240 kc. are differently affected by external interference and that a radio receiver can be adapted for w more effective operation on either of these frequencies if the appropriate tuning unit is applied to the receiving system. I accomplish this by terminating the tuning circuits of the receiver in contact with which contacts associated with a tuning unit may be mated for electrically connecting the appropriate tuning unit in the receiving circuit for rendering such circuit more efficiently responsive to the Conelrad frequency on which minimum of interference exists in the particular area of installation. I provide a transistorized receiving circuit including a transistor receptive to the radio frequency operation and associated with a detecting device; a transistor operating into a rectifying circuit controlling the operation of a relay. A buzzer or other alarm is controlled by this relay. Both the transistorized radio receiver and the alarm include independent power supplies. In the embodiment of my warning device in which batteries are employed as. power supplies I provide special means for checking both the battery in the transistorized radio receiver and the battery in the alarm circuit so that the condition of these batteries may be known at all times. Thus maximum protection is afforded as the owner of the receiver may be confident that it is instantly ready for response to the Conelrad frequencies under conditions of disaster, emergency or sneak attack, forewarned by emissions on the Conelrad frequencies, thereby significantly improving the defense of the nation and reducing hysteria and panic.

In certain embodiments of my invention I provide a transistorized radio receiver and alarm circuit which are i normally powered from the conventional alternating current power supply system. Where, however, the functioning of such supply system may be impaired by destruction or temporary interruption I provide switching means associated with the circuits of the receiver and the alarmsystem for transferring the connectionsof the power supply circuits of the receiver and alarm system to batteries for operation of the circuits in the absence of power supply system from the alternating current.

Referring to the drawings in more detail-reference character 1 designates an antenna system While reference character 2 indicates a ground. A transistor for operation at radio frequencies isdesignated at 3, including a base 4, an emitter 5 and a-collector 6. The emitter 5 and base 4 connect to contacts 7 and S; antenna 1 connects to a contact 9 and ground 2 connects to a contact 10. These contacts 7, 8, 9 and 10 serve as terminals for two readily connectable and disconnectable tuning units one of which is more selectively operative at 640 kc. and the other of which is more elfectively operative at 12 0 kc. One such tuning unit is shown in position in the circuit of FIG. 1 while the replaceable tuning unit is illustrated in FIG. 2. Each tuning unit includes a pair of inductively coupled windings associated through ferrite core 11 with selectively tuning means associated with one of the windings. In FIG. 1 the tuning unit terminates in contacts 12, 13, 14 and 15 which selectively establish connection with the contacts 9, 7, S, and 15, respectively, for selectively connecting the tuning unit represented at 16 in FIG. 1 with the circuits of emitter 5 and base 4 of transistor 3. The components with the tuning unit include the inductive coupled windings 17 and 18 and the variable condenser 19. The entire unit 16 may be removed and the replaceable unit as, shown in FIG. 2, inserted in lieu of unit 16 where unit 16 is more effectively tunable adjacent the 640 kc. band while unit 20 is more eifectively tunable at the 1240 kc. band. The unit 20 is illustrated as containing windings 21 and 22 inductively coupled through ferrite core 11 and where winding 22 is shunted by variable condenser 23. The replaceable unit shown in FIG. 2 has the components thereof terminating in contacts 24, 25, 26 and 27, adapted to mate and establish electrical connection with the contacts 9, 7, 8 and 10, respectively. In both tuning units a variable tap on one of the windings is provided for adjusting the eifective inductance. In unit 16 adjustable tap 28 is provided on winding 18 and connects to contact 13 establishing connection with contact 7 leading to emitter 5. In the tuning unit of FIG. 2 the variable tap is represented at 29 on winding 22 and connects to contact for establishing connection with contact. 7 leading to emitter 5. Thus, the entire tuning unit 16 or 2% is readily removable or insertable into the input circuit of the transistor 3 according to the desired Conelrad frequency on which the receiver is to be operated. The output circuit of transistor 3, leading from collector 6 and base 4 connects to the tuned circuit 30 which connects through resistor 31 to the positive terminal of battery 32, returning to the base 4 of transistor 3. The tuned circuit 3% consists of inductance 33, tuned by condenser 34. Inductance 33 constitutes the primary winding of a radio frequency transformer which is inductively coupled to the secondary winding 35 tuned by condenser 36. A tap 37 on secondary winding 35 leads through the rectifier 35 to the emitter 39 of the transistor 40, the base of which, shown at 41, being connected in common to the input and output circuits of the transistor oil. The collector 42- of transistor 49 connects through another rectifier 43'disposed in a series path with the relay winding 44 returning to the positive side of the battery source 32 as shown.

The relay 44 controls the alarm circuit shown genorally at 45 which includes the battery 46, the relay tongue 47, contact 48, the bell or buzzer 49 and the On and Off" switch 50. When the Conelrad frequency signal activates the radio receiving circuit heretofore explained, relay winding 44 is energized, moving relay tongue 47 to a position closing contact 48, thereby sending the alarm by the continuous operation of the buzzer or bell 49 which is driven from battery 46 and continues to operate so long as the Conelrad frequency persistsor until On and Oil switch 50 is moved to the open position shown.

In order to check the condition of battery 46 I provide a push button switch 51 which is normally biased to open position and which'is connected in shunt with contact 48 and relay tongue 47. By momentarily closing push button switch 51, energy from battery 46 is applied to the hell or buzzer 49 sounding the alarm and thus checking the condition of battery 46.

' the antenna 1 is made to In order to check the condition of the high voltage battery 32, I provide a separate push button switch 52 biased to open position and connected in circuit extending from one side of battery 32 through a dropping resistance 53 to one side of the bell or buzzer 49, the circuit being completed on the other side of the bell or buzzer 49 to the opposite side of battery 32. By momentarily closing switch 5-2 the condition of battery 32 to excite the bell or buzzer 49 may be checked. In testing the high voltage battery 32 sufficient resistance 53 is introduced into the circuit to protect the buzzer or bell 49 and yet provide an indication of the condition of the battery 32.

FIGS. 3 and 4 show the application of my invention to a transistorized receiver of a non-portable type for installation in homes and buildings for maintaining a standby watch on the Conelrad frequencies. In this arrangement the conventional 110 volts AC power supply normally energizes the several circuits of the receiver and the alarm circuit. I have indicated the power supply circuit at 54 leading to a power rectifier and filter, across the output of which potentiometer 55 is shunted. Taps are taken from potentiometer 55 to the alarm circuit and to the circuit of the receiver through the spring and contact assemblies of a double leaf spring relay indicated at 56 operated by relay winding 57 energized through resistor 58 from the power supply circuit 54. The relay 56 includes leaf spring 59 and leaf spring 60 operating between two sets of contacts 61 and 62. Contacts 61 control the connection of either rectified alternating current or battery current from battery 32 to the transistorized receiver. Contacts 62 control the connection of either rectified alternating current or battery power from battery 46 to the alarm circuit 45.

The transistorized receiver comprises four transistor stages, in this form of my invention, two of which are shown at 63 and 64 operating as radio frequency amplifiers, followed by a transistor shown at 65 operating as a detector and one of which is illustrated at 66 operating as an audio frequency amplifier for controlling the relay 4-4 and operating relay tongue 47 for closing the alarm circuit through fixed contact 48 to the bell or buzzer 49.

The tuning unit is similar to that described in FIGS. 1 and 2 in that the unit, efiiciently responsive adjacent the 640 or the 1240 kc. band, may be connected in the input system. This particular tuning unit difiers from the unit shown in FIGS. 1 and 2 in that the connection from a tuned circuit containing an inductance 67 shunted by the condenser 68 and coupled to an inductance 69. Inductance 69 is tuned by the condenser 70 and connects to the emitter 71 of transistor 63. The base 72 of the transistor 63 connects through resistor 73 shunted by condenser 74 to the other end of the tuned circuit 6-70. The tuning unit is connectable and disconnectable from the antenna circuit and the input to the transisto-n'zed receiver through clips in the same manner as described in FIGS. 1 and 2. A connection is established from the collector electrode 77 of transistor 63 through coupling condenser 78 to the emitter '80 of the transistor 64. The collector 77 also connects through a tuned circuit comprising inductance 81 shunted by condenser 82 to ground as shown by which proper bias potential and selectivity is obtained. The emitter of transistor 64 connects to ground through a resistance 83 for securing proper bias. Transistor 64 has its base 84 connected through resistance 85 shunted by condenser 86 to the input coupling resistor 79. The collector S7 of transistor 64 connects through tuned circuit 88 to ground and through'coupling condenser 89 to the emitter91 of transistor 65. The emitter 91 and base 92 of transistor 65 is shunted by resistor 90. V

The base 92 of transistor 65 connects through coupling resistance 93 to theinput circuit of transistor 65 containing coupling resistor 90. The collector 94 of transistor 65 connects through a resistor to ground. The detected signals from the input to the transistor rectifier 65 are passed through coupling condenser 95 and coupling resistor 96 to the emitter 97 of transistor 66. The base 98 of transistor 66 connects through resistor 99 with the input cir cuit of transistor 66 containing coupling resistor 96. The collector tee of transistor 66 connects through resistor 191 shunted by condenser 102 to ground and also to the winding of relay 44 which controls the alarm circuit 45 as heretofore explained. The power circuits for the receiver and the alarm may be normally operated from the conventional 110 volt 60 cycle alternating current supply system as heretofore explained in connection with FIG. 1, or may be switched to the battery supply utilizing battery 46 in the alarm circuit and battery 3-2 in the transistorized receiver circuit as heretofore explained.

I have found the system of my invention highly practical in its operation. When it becomes necessary to test the operating characteristics of the receiver and the alarm I utilize a signal generator set at 640 or 1240 kc. radiating either or both of these frequencies to the receiver to check the triggering off of the receiver and the alarm pursuant to the receipt of these frequencies.

While I have described my invention in certain of its preferred embodiments I realize that'modifications may be made and I desire that it be understood that no limitations upon my invention are intended other than may be imposed by the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent of the United States is as follows:

1. An electrical warning system comprising a transistorized radio receiving circuit selective to a predetermined radio frequency, a relay controlled by said circuit, an alarm controlled by said relay, a power supply circuit connected in said transistorized radio receiving circuit, a power supply circuit connected to said alarm, a battery system for supplying power connected in said power supply circuit of said radio receiving circuit and a separate battery system for supplying power connected in said power supply circuit of said alarm and plural means independent of said relay for individually connecting the said battery systems to said alarm for individually indicating the condition of each of said battery systems by said alarm for maintenance of the operating condition of said warning system.

2. An electrical warning system as set forth in claim 1 in which one of said plural means independent of said relay for connecting said battery system to said alarm comprises a momentary impulse switch connected in parallel with said relay and operative to connect said battery system to said alarm when said relay is in unactuated position.

3. An electrical warning system as set forth in claim 1 in which the other of said plural means independent of said relay for individually connecting the said battery systems to said alarm consists of a circuit extending from said alarm through a resistor and a momentary contact switch to opposite sides of the battery system connected for supplying power to said power supply circuit of said radio receiving circuit for momentarily closing the circuit from said last mentioned battery system to said alarm and a circuit leading from said separate battery system for supplying power to said power supply circuit of said alarm through a momentary contact switch to said alarm.

4. An electrical warning system comprising a transistorized radio receiving circuit selective to a predetermined radio frequency, a relay controlled by said circuit and connected to the output of said circuit, an alarm circuit including an alarm, said relay having a movable contactor connected in said alarm circuit and disposed to complete the alarm circuit and energize the alarm upon receipt of a signal of the predetermined frequency by the radio receiving circuit, a battery power supply connected in said transistorized radio receiving circuit, a separate battery power supply connected in said alarm circuit, a circuit extending from one side of the battery power supply connected in the radio receiving circuit to one side of said alarm, plural means independent of said relay for individually connecting the said battery power supplies to said alarm, one of said plural means comprising a first battery check switch connected in series with said last mentioned circuit and the alarm circuit battery power supply to connect said battery to said alarm when said movable contactor is in open circuit position, the other of said plural means comprising a second battery check switch connected to the opposite side of the radio receiving circuit battery power supply, and a circuit extending from said second check switch to said alarm, said alarm indicating the condition of each of said battery power supplies upon individual closure of said battery check switch for maintenance of the operating condition of said warning system.

5. An electrical warning system as set forth in claim 4- in which said first battery check switchis connected in parallel with the movable contactor of said relay.

References (Iited in the file of this patent UNITED STATES PATENTS 2,009,447 Hart July 30, 1935 2,346,171 Laford Apr. 11, 1944 2,449,168 Kertz Sept. 14, 1948 2,699,493 McCullough Jan. 11, 1955 2,744,194 Auerbach May 1, 1956 2,760,084 Hammond Aug. 21, 1956 2,766,358 Davidson Oct. 9, 1956 2,844,762 Duryee July 22, 1958 

